Hydrogen peroxide is widely known as an excellent hard surface sterilant and disinfectant that is environmentally safe and cost effective. Other sterilant/disinfectant agents such as phenolics and aldehydes are not as environmentally and toxicologically as sound as hydrogen peroxide. For example, although glutaraldehyde compositions are widely used among infection control staff, glutaraldehydes are associated with disadvantages such as skin sensitization, toxicity and chemical waste management.
Despite its superior efficacy for disinfecting and sterilization uses, hydrogen peroxide has not been widely used in medical facilities for cleaning hard metal surfaces because hydrogen peroxide oxidizes metals, such as, copper and brass. Many hospital instruments and scopes contain copper and/or brass components which may become irreversibly damaged by corrosion when exposed to hydrogen peroxide solutions.
Previous attempts to reduce the corrosive affects of hydrogen peroxide solutions have been met with only limited success. For example, when known corrosion inhibitors such as phenyl sulfonic acid, phosphate esters, sodium molybdate, alkanolamines, or benzotriazoles are used, the anti-corrosive activity is either too short-term (because the inhibitor is unstable in the presence of hydrogen peroxide); not observed at all; or the resulting composition leaves an undesirable oxide film residue on hard surfaces upon drying.
In particular, the anti-corrosive agents 1,2,3-benzotriazole and tolyltriazole are known to decrease the corrosive activity of hydrogen peroxide. Both, however, are unstable in the presence of hydrogen peroxide and lose effectiveness after a short storage period. The Comparative Examples hereinafter illustrate the limited stability of 1,2,3-benzotriazole and tolyltriazole in hydrogen peroxide. Hydrogen peroxide compositions with these anti-corrosive agents have a very short shelf life and because the compositions are unstable neither have become accepted compositions useful for cleaning metal surfaces.
Corrosion associated with hydrogen peroxide compositions remains a problem. A stable hydrogen peroxide composition providing a sterilant or disinfectant activity without promoting corrosion to metal surfaces treated with the composition is needed.